The Zika virus was first discovered in a forest in Uganda in 1947--but the first outbreak
in the Americas occurred last May all over Brazil.
There are two theories about it arrived there:
1, it was brought by the crowds of fans arriving for the 2014 World Cup that Brazil hosted
in 12 cities across the country.
Or, 2, a few weeks after the World Cup, it was brought by members of the teams of canoe
racers in the Va’a World Sprint in Rio who had come from several Polynesian Islands.
But regardless of how it got to Brazil, Zika spread rapidly once it was there, infecting
millions of people.
Because no one in the western hemisphere had been exposed to it before--they hadn’t developed
immunity.
It’s transmitted mainly by the extremely common Aedes aegypti mosquito, although there
have been a few cases of it spreading through sex.
80% of people infected have no symptoms, and for the 20% that do, most are mild and flu-like
and don’t last too long.
But some suffer a temporary paralysis called Guillain–Barré syndrome, and for women
who become infected while pregnant things get downright scary, since the spread of Zika
has coincided with an unusual spike in the number of babies born with microcephaly, a
rare congenital condition resulting in an abnormal smallness of the head.
And 80% of those born with microcephaly have incomplete brain development.
But given how quickly the outbreak has popped up and spread, scientists can’t be 100%
sure that Zika is directly causing the uptick in cases of microcephaly, but a more than
1,000% increase in suspected cases in Brazil directly correlating with the explosion of
Zika means they’re preeeetty sure it is.
So to avoid this danger, the American Centers for Disease Control and Prevention is advising
pregnant women to avoid these countries, which correspond with the probable range of the
yellow fever mosquito.
The governments of Colombia and El Salvador have advised women living there to avoid getting
pregnant altogether for the foreseeable future.
It’s also important for everyone there to minimize exposure to mosquito bites.
Débora Diniz, founder of the Brazilian Institute of Bioethics adds this point:
“[Zika] is concentrated among young, poor, black and brown women, a vast majority of
them living in the country’s least-developed regions...They live in substandard, crowded
housing in neighborhoods where stagnant water, the breeding ground for disease-carrying mosquitoes,
is everywhere.”
The crisis also disproportionately burdens poor communities, where women have less access
to birth control, pre- and post-natal medical support, and safe options for abortion, which,
in Brazil for example, are almost always illegal in a country that’s 65% Roman Catholic.
Recently, the World Health Organization declared the Zika virus a global health emergency to
prompt coordinated action to fight it.
The WHO’s proactive response comes after it was heavily criticised for responding too
slowly to the Ebola outbreak of 2014.
Experts say that a place like Haiti, with hardly any public health infrastructure, could
be facing tens of thousands of cases of microcephalic babies by the end of the year if strong, immediate
action isn’t taken.
So the WHO is having to walk a fine line politically between compelling governments to act, and
causing a panic that could hurt the economies of the affected countries, which would compound
their problems.
Rio De Janiero’s hosting of the Summer Olympics in August is the perfect example of the need
to manage the perception of how dangerous Zika really is.
To its credit, the Brazilian government has launched a widespread effort to control its
mosquito population, but that’s not easy in a country that’s home to the world’s
largest forest.
In the United States, where mosquito control programs are widespread and effective, the
risk of a homegrown outbreak appears low.
Still, the CDC predicts Zika to continue spreading in Puerto Rico, with outbreaks in Florida,
some Gulf Coast states and maybe Hawaii.
But despite a surge in media interest surrounding microcephaly and Zika, as of February 2nd,
Brazilian health officials have investigated 23% of the 4,783 suspected cases of microcephaly,
confirming just 404 out of the 1,113 they’ve looked at so far.
So if that rate holds up for the rest of the suspected cases, there will be around 1,700
confirmed cases of microcephaly in Brazil.
It’s a lot harder though to find Zika in these confirmed cases of microcephalic babies,
as only 17 of the 404 have been directly linked to the virus.
This means there’s still a lot of work to be done to solve the mystery of if and how
Zika is causing brain damage in babies.
UC San Francisco virologist Lenore Pereira explains why it’s so important, “if we
understand how the virus infects cells, we can come up with ways to suppress it.”
For the latest information on microcephaly and the Zika virus, check out the link to
the CDC’s website below.
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Until next time, I’m Bryce Plank and, as usual, thanks for watching.